Classification of the Uncertainty of Measurements

A discussion is given of questions arising when classifying uncertainties from the point of view of the structure of the measurement process.     

协同作战能力简析

协同作战能力(CEC)是一种充分利用网络技术的新型海岸防空技术，给系统的作战能力带来了革命性的交破。本文对协同作战能力的产生、功能、组成以及未来的发展趋势作了详细的介绍，阐述了CEC系统的总体设计思想。在此基础上，将CEC系统与传统的作战系统的性能和设计思想在各方面进行了比较，交出了CEC系统各方面的优越性能。协同作战能力是现代和未来作战系统的发展方向，CEC系统的发展必将成为衡量各国国防科技现代化的重要指标。     

数学归纳法的几个推广

将通常适用于自然数系的数学归纳法推广到了下有界整数集{n|n∈Z,n≥n0}与上有界整数集{n|n∈Z，n≤m0}及全体整数集Z。并证明了关于命题{P(m,n)}m,n∈z的二元数学归纳法。     

可拓检测的方案生成

以可拓学理论为基础，论述了可拓检测的有关定义和概念，提出了可拓检测的方案生成方法及过程，同时探讨了检测方法的优化和评价方法。     

Efficiency of repeated batch penicillin fermentation using two fermentors. Computer simulation and optimisation

Repeated batch operation using two fermentors (RBTF) to penicillin fermentation was demonstrated by computer simulation to improve productivity. Three operation modes were compared: chemostat, repeated batch operation using a single fermentor (RBSF) and RBTF; in each case account was made of the lag period before growth. The simulated fermentor performances were assessed on the basis of the penicillin productivity and concentration; the simulation was based on published batch fermentation data. It was shown that RBTF was superior to RBSF and chemostat. The advantage of RBTF increased as the lag period became greater.     

电视机监督检验电磁兼容结果分析和对策

本文讨论了电磁兼容对电视机的技术要求和相应对策。     

三峡地下电站变顶高尾水洞水动力特性

在国内首次应用模型水轮发电机组对三峡地下电站变顶高尾水洞方案进行水力过渡过程试验研究。对水轮机导叶实行分段关闭 ,并求出了二段关闭的最佳拐点 ,试验证实了二段关闭对减小尾水管进口的负压和机组转速上升有明显的作用。通过有关水力参数的测试 ,认为变顶高尾水洞可以满足各项技术要求 ,是一个减少山体开挖、节省投资的新型设计方案。在地下电站中具有广泛的应用前景     

The solution of the inverse problem of gravitational potential using a set of measurements of different field elements

A numerical solution of the inverse problem of the gravitational field at a single point is obtained using six field elements for a point, a spherical cap, a differential spherical sector and a vertical segment. In the system of six equations obtained, the unknowns are the mass of the body, the depth of its center, and the second, third, and fourth degree moments. The accuracy of the solution of this system is ten times higher than when using three field elements. __________ Translated from Izmeritel’naya Tekhnika, No. 5, pp. 3–8, May, 2007.     

A new distributed approximation algorithm for constructing minimum connected dominating set in wireless ad hoc networks

In recent years, constructing a virtual backbone by nodes in a connected dominating set (CDS) has been proposed to improve the performance of ad hoc wireless networks. In general, a dominating set satisfies that every vertex in the graph is either in the set or adjacent to a vertex in the set. A CDS is a dominating set that also induces a connected sub‐graph. However, finding the minimum connected dominating set (MCDS) is a well‐known NP‐hard problem in graph theory. Approximation algorithms for MCDS have been proposed in the literature. Most of these algorithms suffer from a poor approximation ratio, and from high time complexity and message complexity. In this paper, we present a new distributed approximation algorithm that constructs a MCDS for wireless ad hoc networks based on a maximal independent set (MIS). Our algorithm, which is fully localized, has a constant approximation ratio, and O(n) time and O(n) message complexity. In this algorithm, each node only requires the knowledge of its one‐hop neighbours and there is only one shortest path connecting two dominators that are at most three hops away. We not only give theoretical performance analysis for our algorithm, but also conduct extensive simulation to compare our algorithm with other algorithms in the literature. Simulation results and theoretical analysis show that our algorithm has better efficiency and performance than others. Copyright © 2005 John Wiley & Sons, Ltd.